Aluminum alloy



Patented July 21 I925.

'rnxarnsu manna, or xYo'ro, JAPAN.

nnumum Anno llo Drawing.

7'0 all whom zt may concern:

Be it known that I, TAKAYASU HARADA, a subject of the Empire of Japan,residing at care of Institute of illletallurgy, College of Engineering,Kyoto Imperial University,

Kyoto, Japan, have invented certain new and useful Improvements inAluminum Alloys, of which the following is a specifica-. tion.

This invention relates to an alloy containing Ou:0.3-6%, Ni: 0.545%, Mn:05- 0% the remainder being aluminum. The particular object of thisinvention is to produce an aluminum alloy resistant to weak acids, ll!vsolutions of salts and weak alkalis, having great hardness, strength andductility.

The composition of this alloy is 00:03- 6%, Ni: 0.543%, Mn 0.56%, thebalance being aluminum. v 1

The method of manufacture is as follows :Prepare beforehand three hard!eners, i. e. the first hardener is an alloy of A1:Cu:: 75 :25, thesecond hardener is an alloy of A1:Ni:: 75 and the'third hardener is analloy of Alzlllnn :25..

An amount of aluminum metal is first melted in a graphite crucible in acoke'furnace atabout 800 C. amounts of the three add the calculatedhardeners in it, and

agitate well with an iron rod. If they mixed as in the case 0homogeneously, take the crucible out of the furnace, put a littlezinc-chloride on the surface of the molten alloy and take off the reaterpart of the slag, cool to about 700 and cast in-iron chill-moulds, toform slabs. j i

Rolling and pressing may be carried out aluminum metal. At present it isdiflicult to separate small rcentages of iron from aluminum. Itsinfluence on aluminum are (1) it makes aluminum very corrosive, (2) itstains the surface of aluminum with black or dirty compounds when brg htin contact wit even weak organic ac or. some salts, (3) it s ils themechanical properties of aluminum. 0.345% of copper in this alloyrelieves all these ill-effects of iron perfectly, H

promotes mechanical properties and and resistivit t0 corrosion. 4

The a by of aluminum and manganese is very resistant to corrosion andhas a minute grain point of this alloy, the grains of the alloy areevidently minute and do not grow larger even after long use. I

structure. Near the eutectic- Applicatlon fllcd June 4, 1924. Serial No.717,845.

Nickel in this alloy also has the same efiect as'manganese and copperand makes a more resistant alloy having a more minute grain structurethan that containing no 60 nickel.

As above mentioned, this alloyis almost absolutely non-corrosive when incontact with organic acids, .solution of salts and alkalis (exceptcaustic alkalis), and also inorganic acids. V

The examples of resistance. to corrosion are shown in Table 1 and itsmechanical properties are shown in Table '2. TABLE 1.'0orr0sion testsincome-examples.

(B) G Cu.... 1. 0 6a.... 1. n 'Cu... 11-... 11-... -Ana3ysls Fen" Fan 0,0,

.06 Si"-.. 0 06 0 S1....

Al: balance. 1 111:

For 30 days, at room temperature, dipped in these reagent: 7

a 057 NH 0H {%o110ss inwt 0.0000 0.0014 0. 1 Gr. otlosspersq. cm..--0.00000 0.00001 0.00001 37 N80] '{%ollossinwt 0. 0.0000 0.1!!!) Gr.otloss persq. cm.... 0.00000 0.00000 0.00000 a7 Nmcm %oflosslnwt 0.00600.0065 0.1034

Gr. oflosspersq.c1n 0.00003 0.00004 0.00002 3% citric and %oflossinwt0.0000 0.0029 0.0032

malic acids.-- Gr. efloss per sq. cm 0.00000 0.0003 0.00002 Na Sm%oflossmwt 0.0000 0.0000 0.11113 0 Gr. ofloss persq. can... 0.000000.00000 0.00001 Japanese %of1ossinwt 0.0000 0.0000 0.0000

oyu Gr. 011m per sq; cm.... 0.00000 0.00000 0.00000 Japanese %o[loss1nwt0.0000 0.0000 0.01110 scr e ass 0 use n 5 mm 3:. of loss pg't sq. 0mm. goom agi x aa gg i 05$ dnouoss per sq. 0111---- 0.00010 000000 0.00004%0[l0SSiDWl I .3052 1.3103 1.0030 Gr.o1'1osspersq. 01m... 0.000950.00554 0.00136 .0'57' H o 011085 in .2845 1.3745' 1.0014

0 1-. otloss-per sq. 05.--- 0.00758 000500 0.00040 057 BN0 7 ollossmwt1.1064 1.1066 1.0851.

- v dr. ol'losspersq. 0111---- 0.00678 000078 00113 0. N. B. Shoyu is akind or sauce made from common salt and TABLE 2. -MechanicaZ tests of anexample.

Analysis .-Cu:1.48'7$ N1: 2.00%, Mn:2.37%, Fe: 0.47%.

- S1: 0.0! A]: Balance. cold worked.....2)34 k mm or 12.8-21.7 Tensilestrength in (thin plate) annealed .-l8. g- 2f k z l mm or 11.0-14.7 Eloetlon 7J2 cold worked a 1n (thlnfilste annealed. 10-13 a ardness rin cNo. with 500k; dworked 05-70 p e lhlck- Depthness. olcup.

I 0.3mm 2.86m!!! coldworxed 0.4mm 3.25m Clgfih i testswith' 0.6mm 3.65mmc ontest.-... 0.3mm Lemma 4 annealed 0.4mm 068mm 0. 5mm 6.81m

In conclusion, the special properties of corrosive when in contact withorganic ac1ds,'weak'alkal1s and solutlon 'of many of the alloy are veryminute; (3) its mechanlcal propertles are very superior; (4:) impurealuminum lng'ots can be used to I make this alloy.

As a result, this alloy is inost suitable to make utensils which areused in contact with 7 weak acids, alkalis" on solutions of salts,

especially for kitchenwares.

I claim An aluminum alloy containing 0.3-6% of copper, 0.56% of nickel,0.5-6% of manganese the 'balance being, aluminum and impurities.

In witness whereof I have signed this specification in presence of twowitnesses.

Dated this 8th day of May, 1924.

TAKAYASU HARADA.

Witnesses:

- G. T. OGATA,

IOHIRO SUDZUKI.

